sentence = 'tom\'s pet is a cat'
sentence2 = "tom's pet is a cat"
sentence3 = "tom said:\"hello world!\""
sentence4 = 'tom said:"hello world"'
print(f'sentence: {sentence}')
print(f'sentence2: {sentence2}')
print(f'sentence3: {sentence3}')
print(f'senctence4: {sentence4}')
words = """
hello
world
abcd"""
print(words)

py_str = 'python'
print(len(py_str))
print(py_str[0])
print('python'[0])
print(py_str[-1])
print(py_str[2:4])
print(py_str[2:])
print(py_str[:2])
print(py_str[:])
print(py_str[::2])
print(py_str[1::2])
print(py_str[::-1])

print(py_str + 'is good')
print(py_str * 3)

print('t' in py_str)
print('th' in py_str)
print('to' in py_str)
print('to' not in py_str)
